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* 8.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef listBruce Momjian2009-06-11
| | | | provided by Andrew.
* Refactor ExecProject and associated routines so that fast-path code is usedTom Lane2009-04-02
| | | | | | | | | for simple Var targetlist entries all the time, even when there are other entries that are not simple Vars. Also, ensure that we prefetch attributes (with slot_getsomeattrs) for all Vars in the targetlist, even those buried within expressions. In combination these changes seem to significantly reduce the runtime for cases where tlists are mostly but not exclusively Vars. Per my proposal of yesterday.
* Update copyright for 2009.Bruce Momjian2009-01-01
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* As noted by Andrew Gierth, there's really no need any more to force a junkTom Lane2008-07-26
| | | | | | | | | | | | | | | | filter to be used when INSERT or SELECT INTO has a plan that returns raw disk tuples. The virtual-tuple-slot optimizations that were put in place awhile ago mean that ExecInsert has to do ExecMaterializeSlot, and that already copies the tuple if it's raw (and does so more efficiently than a junk filter, too). So get rid of that logic. This in turn means that we can throw away ExecMayReturnRawTuples, which wasn't used for any other purpose, and was always a kluge anyway. In passing, move a couple of SELECT-INTO-specific fields out of EState and into the private state of the SELECT INTO DestReceiver, as was foreseen in an old comment there. Also make intorel_receive use ExecMaterializeSlot not ExecCopySlotTuple, for consistency with ExecInsert and to possibly save a tuple copy step in some cases.
* Move the HTSU_Result enum definition into snapshot.h, to avoid includingAlvaro Herrera2008-03-26
| | | | | | tqual.h into heapam.h. This makes all inclusion of tqual.h explicit. I also sorted alphabetically the includes on some source files.
* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
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* Avoid incrementing the CommandCounter when CommandCounterIncrement is calledTom Lane2007-11-30
| | | | | | | | | | | | | | | | | | | | but no database changes have been made since the last CommandCounterIncrement. This should result in a significant improvement in the number of "commands" that can typically be performed within a transaction before hitting the 2^32 CommandId size limit. In particular this buys back (and more) the possible adverse consequences of my previous patch to fix plan caching behavior. The implementation requires tracking whether the current CommandCounter value has been "used" to mark any tuples. CommandCounter values stored into snapshots are presumed not to be used for this purpose. This requires some small executor changes, since the executor used to conflate the curcid of the snapshot it was using with the command ID to mark output tuples with. Separating these concepts allows some small simplifications in executor APIs. Something for the TODO list: look into having CommandCounterIncrement not do AcceptInvalidationMessages. It seems fairly bogus to be doing it there, but exactly where to do it instead isn't clear, and I'm disinclined to mess with asynchronous behavior during late beta.
* pgindent run for 8.3.Bruce Momjian2007-11-15
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* HOT updates. When we update a tuple without changing any of its indexedTom Lane2007-09-20
| | | | | | | | | | | | columns, and the new version can be stored on the same heap page, we no longer generate extra index entries for the new version. Instead, index searches follow the HOT-chain links to ensure they find the correct tuple version. In addition, this patch introduces the ability to "prune" dead tuples on a per-page basis, without having to do a complete VACUUM pass to recover space. VACUUM is still needed to clean up dead index entries, however. Pavan Deolasee, with help from a bunch of other people.
* Arrange to cache a ResultRelInfo in the executor's EState for relations thatTom Lane2007-08-15
| | | | | | | | | | | | | are not one of the query's defined result relations, but nonetheless have triggers fired against them while the query is active. This was formerly impossible but can now occur because of my recent patch to fix the firing order for RI triggers. Caching a ResultRelInfo avoids duplicating work by repeatedly opening and closing the same relation, and also allows EXPLAIN ANALYZE to "see" and report on these extra triggers. Use the same mechanism to cache open relations when firing deferred triggers at transaction shutdown; this replaces the former one-element-cache strategy used in that case, and should improve performance a bit when there are deferred triggers on a number of relations.
* If we're gonna use ExecRelationIsTargetRelation here, might as wellTom Lane2007-07-31
| | | | simplify a bit further.
* Slight refactor for ExecOpenScanRelation(): we can useNeil Conway2007-07-27
| | | | | ExecRelationIsTargetRelation() to check if the relation is a target rel, rather than scanning through the result relation array ourselves.
* Get rid of the separate EState for subplans, and just let them share theTom Lane2007-02-27
| | | | | | | | | parent query's EState. Now that there's a single flat rangetable for both the main plan and subplans, there's no need anymore for a separate EState, and removing it allows cleaning up some crufty code in nodeSubplan.c and nodeSubqueryscan.c. Should be a tad faster too, although any difference will probably be hard to measure. This is the last bit of subsidiary mop-up work from changing to a flat rangetable.
* Turn the rangetable used by the executor into a flat list, and avoid storingTom Lane2007-02-22
| | | | | | | | | | | | | | | | | useless substructure for its RangeTblEntry nodes. (I chose to keep using the same struct node type and just zero out the link fields for unneeded info, rather than making a separate ExecRangeTblEntry type --- it seemed too fragile to have two different rangetable representations.) Along the way, put subplans into a list in the toplevel PlannedStmt node, and have SubPlan nodes refer to them by list index instead of direct pointers. Vadim wanted to do that years ago, but I never understood what he was on about until now. It makes things a *whole* lot more robust, because we can stop worrying about duplicate processing of subplans during expression tree traversals. That's been a constant source of bugs, and it's finally gone. There are some consequent simplifications yet to be made, like not using a separate EState for subplans in the executor, but I'll tackle that later.
* Remove the Query structure from the executor's API. This allows us to stopTom Lane2007-02-20
| | | | | | | | | | | | | | | storing mostly-redundant Query trees in prepared statements, portals, etc. To replace Query, a new node type called PlannedStmt is inserted by the planner at the top of a completed plan tree; this carries just the fields of Query that are still needed at runtime. The statement lists kept in portals etc. now consist of intermixed PlannedStmt and bare utility-statement nodes --- no Query. This incidentally allows us to remove some fields from Query and Plan nodes that shouldn't have been there in the first place. Still to do: simplify the execution-time range table; at the moment the range table passed to the executor still contains Query trees for subqueries. initdb forced due to change of stored rules.
* Remove typmod checking from the recent security-related patches. It turnsTom Lane2007-02-06
| | | | | | | | | | | | | out that ExecEvalVar and friends don't necessarily have access to a tuple descriptor with correct typmod: it definitely can contain -1, and possibly might contain other values that are different from the Var's value. Arguably this should be cleaned up someday, but it's not a simple change, and in any case typmod discrepancies don't pose a security hazard. Per reports from numerous people :-( I'm not entirely sure whether the failure can occur in 8.0 --- the simple test cases reported so far don't trigger it there. But back-patch the change all the way anyway.
* Repair failure to check that a table is still compatible with a previouslyTom Lane2007-02-02
| | | | | | | | | | | | | | | | | | | | | | made query plan. Use of ALTER COLUMN TYPE creates a hazard for cached query plans: they could contain Vars that claim a column has a different type than it now has. Fix this by checking during plan startup that Vars at relation scan level match the current relation tuple descriptor. Since at that point we already have at least AccessShareLock, we can be sure the column type will not change underneath us later in the query. However, since a backend's locks do not conflict against itself, there is still a hole for an attacker to exploit: he could try to execute ALTER COLUMN TYPE while a query is in progress in the current backend. Seal that hole by rejecting ALTER TABLE whenever the target relation is already open in the current backend. This is a significant security hole: not only can one trivially crash the backend, but with appropriate misuse of pass-by-reference datatypes it is possible to read out arbitrary locations in the server process's memory, which could allow retrieving database content the user should not be able to see. Our thanks to Jeff Trout for the initial report. Security: CVE-2007-0556
* Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian2007-01-05
| | | | back-stamped for this.
* Fix failure due to accessing an already-freed tuple descriptor in a planTom Lane2006-12-26
| | | | | | | | | | | | involving HashAggregate over SubqueryScan (this is the known case, there may well be more). The bug is only latent in releases before 8.2 since they didn't try to access tupletable slots' descriptors during ExecDropTupleTable. The least bogus fix seems to be to make subqueries share the parent query's memory context, so that tupdescs they create will have the same lifespan as those of the parent query. There are comments in the code envisioning going even further by not having a separate child EState at all, but that will require rethinking executor access to range tables, which I don't want to tackle right now. Per bug report from Jean-Pierre Pelletier.
* pgindent run for 8.2.Bruce Momjian2006-10-04
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* Fix domain_in() bug exhibited by Darcy Buskermolen. The idea of an EStateTom Lane2006-08-04
| | | | | | | | | | | | | that's shorter-lived than the expression state being evaluated in it really doesn't work :-( --- we end up with fn_extra caches getting deleted while still in use. Rather than abandon the notion of caching expression state across domain_in calls altogether, I chose to make domain_in a bit cozier with ExprContext. All we really need for evaluating variable-free expressions is an ExprContext, not an EState, so I invented the notion of a "standalone" ExprContext. domain_in can prevent resource leakages by doing a ReScanExprContext on this rather than having to free it entirely; so we can make the ExprContext have the same lifespan (and particularly the same per_query memory context) as the expression state structs.
* Change the relation_open protocol so that we obtain lock on a relationTom Lane2006-07-31
| | | | | | | | | | | | (table or index) before trying to open its relcache entry. This fixes race conditions in which someone else commits a change to the relation's catalog entries while we are in process of doing relcache load. Problems of that ilk have been reported sporadically for years, but it was not really practical to fix until recently --- for instance, the recent addition of WAL-log support for in-place updates helped. Along the way, remove pg_am.amconcurrent: all AMs are now expected to support concurrent update.
* Remove 576 references of include files that were not needed.Bruce Momjian2006-07-14
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* Sort reference of include files, "A" - "F".Bruce Momjian2006-07-11
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* Fix problems with cached tuple descriptors disappearing while still in useTom Lane2006-06-16
| | | | | | | | | | by creating a reference-count mechanism, similar to what we did a long time ago for catcache entries. The back branches have an ugly solution involving lots of extra copies, but this way is more efficient. Reference counting is only applied to tupdescs that are actually in caches --- there seems no need to use it for tupdescs that are generated in the executor, since they'll go away during plan shutdown by virtue of being in the per-query memory context. Neil Conway and Tom Lane
* Improve the representation of FOR UPDATE/FOR SHARE so that we canTom Lane2006-04-30
| | | | | | support both FOR UPDATE and FOR SHARE in one command, as well as both NOWAIT and normal WAIT behavior. The more general code is actually simpler and cleaner.
* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-05
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* Some minor code cleanup, falling out from the removal of rtree. SK_NEGATETom Lane2006-01-14
| | | | | | | | | | | | isn't being used anywhere anymore, and there seems no point in a generic index_keytest() routine when two out of three remaining access methods aren't using it. Also, add a comment documenting a convention for letting access methods define private flag bits in ScanKey sk_flags. There are no such flags at the moment but I'm thinking about changing btree's handling of "required keys" to use flag bits in the keys rather than a count of required key positions. Also, if some AM did still want SK_NEGATE then it would be reasonable to treat it as a private flag bit.
* Tweak indexscan machinery to avoid taking an AccessShareLock on an indexTom Lane2005-12-03
| | | | | | | if we already have a stronger lock due to the index's table being the update target table of the query. Same optimization I applied earlier at the table level. There doesn't seem to be much interest in the more radical idea of not locking indexes at all, so do what we can ...
* Adjust scan plan nodes to avoid getting an extra AccessShareLock on aTom Lane2005-12-02
| | | | | | relation if it's already been locked by execMain.c as either a result relation or a FOR UPDATE/SHARE relation. This avoids an extra trip to the shared lock manager state. Per my suggestion yesterday.
* Get rid of ExecAssignResultTypeFromOuterPlan() and make all plan node typesTom Lane2005-11-23
| | | | | | | | | | | generate their output tuple descriptors from their target lists (ie, using ExecAssignResultTypeFromTL()). We long ago fixed things so that all node types have minimally valid tlists, so there's no longer any good reason to have two different ways of doing it. This change is needed to fix bug reported by Hayden James: the fix of 2005-11-03 to emit the correct column names after optimizing away a SubqueryScan node didn't work if the new top-level plan node used ExecAssignResultTypeFromOuterPlan to generate its tupdesc, since the next plan node down won't have the correct column labels.
* Re-run pgindent, fixing a problem where comment lines after a blankBruce Momjian2005-11-22
| | | | | | | | | comment line where output as too long, and update typedefs for /lib directory. Also fix case where identifiers were used as variable names in the backend, but as typedefs in ecpg (favor the backend for indenting). Backpatch to 8.1.X.
* Prevent ExecInsert() and ExecUpdate() from scribbling on the result tupleTom Lane2005-11-14
| | | | | | | slot of the topmost plan node when a trigger returns a modified tuple. These appear to be the only places where a plan node's caller did not treat the result slot as read-only, which is an assumption that nodeUnique makes as of 8.1. Fixes trigger-vs-DISTINCT bug reported by Frank van Vugt.
* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
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* Add NOWAIT option to SELECT FOR UPDATE/SHARE.Tom Lane2005-08-01
| | | | | Original patch by Hans-Juergen Schoenig, revisions by Karel Zak and Tom Lane.
* Avoid WAL-logging individual tuple insertions during CREATE TABLE ASTom Lane2005-06-20
| | | | | | (a/k/a SELECT INTO). Instead, flush and fsync the whole relation before committing. We do still need the WAL log when PITR is active, however. Simon Riggs and Tom Lane.
* Implement sharable row-level locks, and use them for foreign key referencesTom Lane2005-04-28
| | | | | | | | | | | | | | | to eliminate unnecessary deadlocks. This commit adds SELECT ... FOR SHARE paralleling SELECT ... FOR UPDATE. The implementation uses a new SLRU data structure (managed much like pg_subtrans) to represent multiple- transaction-ID sets. When more than one transaction is holding a shared lock on a particular row, we create a MultiXactId representing that set of transactions and store its ID in the row's XMAX. This scheme allows an effectively unlimited number of row locks, just as we did before, while not costing any extra overhead except when a shared lock actually has to be shared. Still TODO: use the regular lock manager to control the grant order when multiple backends are waiting for a row lock. Alvaro Herrera and Tom Lane.
* Remove explicit FreeExprContext calls during plan node shutdown. TheTom Lane2005-04-23
| | | | | | | | | | | | ExprContexts will be freed anyway when FreeExecutorState() is reached, and letting that routine do the work is more efficient because it will automatically free the ExprContexts in reverse creation order. The existing coding was effectively freeing them in exactly the worst possible order, resulting in O(N^2) behavior inside list_delete_ptr, which becomes highly visible in cases with a few thousand plan nodes. ExecFreeExprContext is now effectively a no-op and could be removed, but I left it in place in case we ever want to put it back to use.
* Completion of project to use fixed OIDs for all system catalogs andTom Lane2005-04-14
| | | | | | | indexes. Replace all heap_openr and index_openr calls by heap_open and index_open. Remove runtime lookups of catalog OID numbers in various places. Remove relcache's support for looking up system catalogs by name. Bulky but mostly very boring patch ...
* Merge Resdom nodes into TargetEntry nodes to simplify code and save aTom Lane2005-04-06
| | | | | | | | | few palloc's. I also chose to eliminate the restype and restypmod fields entirely, since they are redundant with information stored in the node's contained expression; re-examining the expression at need seems simpler and more reliable than trying to keep restype/restypmod up to date. initdb forced due to change in contents of stored rules.
* Convert index-related tuple handling routines from char 'n'/' ' to boolTom Lane2005-03-21
| | | | | | | | | | convention for isnull flags. Also, remove the useless InsertIndexResult return struct from index AM aminsert calls --- there is no reason for the caller to know where in the index the tuple was inserted, and we were wasting a palloc cycle per insert to deliver this uninteresting value (plus nontrivial complexity in some AMs). I forced initdb because of the change in the signature of the aminsert routines, even though nothing really looks at those pg_proc entries...
* Revise TupleTableSlot code to avoid unnecessary construction and disassemblyTom Lane2005-03-16
| | | | | | | | | | | | | | | | | | | | | of tuples when passing data up through multiple plan nodes. A slot can now hold either a normal "physical" HeapTuple, or a "virtual" tuple consisting of Datum/isnull arrays. Upper plan levels can usually just copy the Datum arrays, avoiding heap_formtuple() and possible subsequent nocachegetattr() calls to extract the data again. This work extends Atsushi Ogawa's earlier patch, which provided the key idea of adding Datum arrays to TupleTableSlots. (I believe however that something like this was foreseen way back in Berkeley days --- see the old comment on ExecProject.) A test case involving many levels of join of fairly wide tables (about 80 columns altogether) showed about 3x overall speedup, though simple queries will probably not be helped very much. I have also duplicated some code in heaptuple.c in order to provide versions of heap_formtuple and friends that use "bool" arrays to indicate null attributes, instead of the old convention of "char" arrays containing either 'n' or ' '. This provides a better match to the convention used by ExecEvalExpr. While I have not made a concerted effort to get rid of uses of the old routines, I think they should be deprecated and eventually removed.
* Tag appropriate files for rc3PostgreSQL Daemon2004-12-31
| | | | | | | | Also performed an initial run through of upgrading our Copyright date to extend to 2005 ... first run here was very simple ... change everything where: grep 1996-2004 && the word 'Copyright' ... scanned through the generated list with 'less' first, and after, to make sure that I only picked up the right entries ...
* Adjust index locking rules as per my proposal of earlier today. YouTom Lane2004-09-30
| | | | | | now are supposed to take some kind of lock on an index whenever you are going to access the index contents, rather than relying only on a lock on the parent table.
* Renumber SnapshotNow and the other special snapshot codes so thatTom Lane2004-09-11
| | | | | | | | ((Snapshot) NULL) can no longer be confused with a valid snapshot, as per my recent suggestion. Define a macro InvalidSnapshot for 0. Use InvalidSnapshot instead of SnapshotAny as the do-nothing special case for heap_update and heap_delete crosschecks; this seems a little cleaner even though the behavior is really the same.
* Pgindent run for 8.0.Bruce Momjian2004-08-29
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* Update copyright to 2004.Bruce Momjian2004-08-29
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* Use the new List API function names throughout the backend, and disable theNeil Conway2004-05-30
| | | | | list compatibility API by default. While doing this, I decided to keep the llast() macro around and introduce llast_int() and llast_oid() variants.
* Reimplement the linked list data structure used throughout the backend.Neil Conway2004-05-26
| | | | | | | | | | | | | | | | In the past, we used a 'Lispy' linked list implementation: a "list" was merely a pointer to the head node of the list. The problem with that design is that it makes lappend() and length() linear time. This patch fixes that problem (and others) by maintaining a count of the list length and a pointer to the tail node along with each head node pointer. A "list" is now a pointer to a structure containing some meta-data about the list; the head and tail pointers in that structure refer to ListCell structures that maintain the actual linked list of nodes. The function names of the list API have also been changed to, I hope, be more logically consistent. By default, the old function names are still available; they will be disabled-by-default once the rest of the tree has been updated to use the new API names.
* Reimplement CASE val WHEN compval1 THEN ... WHEN compval2 THEN ... ENDTom Lane2004-03-17
| | | | | | | | so that the 'val' is computed only once, per recent discussion. The speedup is not much when 'val' is just a simple variable, but could be significant for larger expressions. More importantly this avoids issues with multiple evaluations of a volatile 'val', and it allows the CASE expression to be reverse-listed in its original form by ruleutils.c.
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